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Spectroscopy study of metal complexes with terpyridyl ligands
Kožíšek, Jan ; Šloufová, Ivana (advisor) ; Procházka, Marek (referee)
The work is focused on preparation and characterization of octahedral Fe(II) complexes of 2,2′:6′,2′′-terpyridine (tpy) substituted in 4' position by various groups: Cl (tpyCl), chlorophenyl (tpyPhCl) and 2-thienyl (Ttpy)). Formation and stability of prepared complexes were studied by UV/vis spectroscopy on the basis of titration of tpy ligands by Fe(II) ions. The molar absorption coefficient of the metal-to-ligand charge transfer (MLCT) band was found to increase in the order: tpy < tpyCl < tpyPhCl < Ttpy. The MLCT band position increases in the same order, starting from 551 nm for [Fe(tpy)2]2+ to 576 nm for [Fe(Ttpy)2]2+ . Raman scattering (RS) spectra of tpy ligands were obtained upon non-resonance 780 nm excitation. Four excitation wavelengths (445, 532, 633 a 780 nm) were used for measurement Fe(II) complexes. The excitation profiles of both Raman scattering and surface-enhanced Raman scattering (SERS) spectra were constructed for [Fe(tpyCl)2]2+ complex. On the basis of DFT calculations performed for this complex, the Raman active modes have been assigned to the symmetry species of the D2d point group. Similarly as for the previously studied [Fe(tpy)2]2+ complex, activation of E modes in the region of MLCT band suggests contribution of Herzberg-Teller mechanism to the overall molecular...
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Self-inflicting in Adolescence
Procházka, Marek ; Sivek, Vojtěch (advisor) ; Klimešová, Anna (referee)
SelfHinflicting is intentional harming, hurting and injuring one ́s own body without clear intention to die. The most common method is cutting wrist, forearm and burning oneself. Motivation can be facing up to some sudden hard situation, without repeating this behaviour or recurrence and even addiction on this selfHinflicting. In danger are mostly adolescents who are evolving and capturing experience in solving hard situations. The need of love, relationships and safety are relating to this. They often experience the disilussion in these areas. The research proved that selfHinflicting is in the adolescent group known phenomenon and some of them have their own experience or practise it regularly. Powered by TCPDF (www.tcpdf.org)
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SERS spectroscopy of model biomolecules for SERS biosensing
Šubr, Martin ; Procházka, Marek (advisor) ; Michl, Martin (referee)
Title: SERS spectroscopy of model biomolecules for SERS biosensing Author: Martin Šubr Department: Institute of Physics of Charles University Supervisor: doc. RNDr. Marek Procházka, Dr., Institute of Physics of Charles University Abstract: The main requirement for surface enhanced Raman scattering (SERS)-based biomolecular sensing is high sensitivity and spectral reproducibility. For this purpose, ordered silver and gold nanostructures fabricated by magnetron sputtering and lithography methods at cooperating institutes were tested in this work. Reproducible SERS spectra of employed model biomolecules (amino acids, lysozyme and albumin) were obtained on ordered silver surfaces at concentrations 10-4 M - 10-6 M and as low as ≈ 10-7 M in the case of porphyrins. SERS spectra of certain biomolecules were also compared to spectra measured on silver colloid. The limit of detection provided by hydroxylamine-reduced silver colloid, using KCl as an aggregating agent, is substantially lower (on the order of 10-8 M for cysteine), but with lower spectral reproducibility. The main drawback of SERS spectra measured on silver surfaces was the occurrence of spurious bands resulting from the preparation procedure. In the case of sputter-deposited silver surfaces, it was found that keeping the substrates several hours in...
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Optical responses of biomolecules on regular metal plasmonic nanostructures
Šubr, Martin ; Procházka, Marek (advisor) ; Michl, Martin (referee) ; Valenta, Jan (referee)
Title: Optical Responses of Biomolecules on Regular Metal Plasmonic Nanostructures Author: Martin Šubr Department: Institute of Physics of Charles University Supervisor of the doctoral thesis: prof. RNDr. Marek Procházka, Dr., Institute of Physics of Charles University Abstract: Adsorption of molecules on metal plasmonic nanostructures leads to significant enhancement of many optical processes, such as Raman scattering (surface-enhanced Raman scattering - SERS) or fluorescence (surface-enhanced fluorescence - SEF). Two groups of substrates were tested within this thesis: (i) Silver nanorods prepared by oblique angle vapor deposition, and (ii) silver and gold nanoislands growing on magnetron-sputtered polytetrafluoroethylene film. Step-by- step optimization process was performed on the nanoislands in order to obtain optimum SERS sensitivity and reproducibility. Detailed SERS intensity profiles were obtained using gradient nanostructures with the localized surface plasmon resonance (LSPR) condition varying across the sample and three different excitation wavelengths. It was also found that spectral position and height of the LSPR band can be controlled simultaneously using mixed gold/silver nanoislands. Detailed investigation of polarization- and angular- dependences of anisotropic silver nanorods was...
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Study of biomolecules by Surface-enhanced Raman microspectroscopy
Šimáková, Petra ; Procházka, Marek (advisor) ; Šmejkal, Petr (referee)
This work deals with study of biomolecules using surface-enhanced Raman scattering (SERS) microspectroscopy. For that purpose surfaces based on gold and silver colloidal nanoparticles immobilized either by silane or by drying on glass plate were tested. As a model molecule cationic free-base 5,10,15,20-tetrakis(1-methyl-4-pyridyl)porphyrin was chosen. The aim was primarily to improve sensitivity and spectral reproducibility of the mentioned SERS-active systems using an integrated Raman microspectrometer which has several advantages (better signal-to-noise ratio, shorter collection time, mapping, confocality) over a classical Raman spectrometer. The obtained results show that gold and silver nanoparticles immobilized by silane give the limits of detection of porphyrin ~ 1×10-8 M, moreover in the intact free-base form. While gold surfaces also show excellent spectral reproducibility, in the case of silver surfaces there is a great problem of frequent presence of spurious bands originating apparently from contamination by carbonaceous compounds and decomposition of silane or porphyrin itself. In the case of silver nanoparticles, drops that form a ring of aggregates with extremely high SERS enhancement after drying on glass proved more suitable.
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Surface-enhanced Raman microspectroscopy of biomolecules and biological systems
Šimáková, Petra ; Procházka, Marek (advisor) ; Michl, Martin (referee) ; Šloufová, Ivana (referee)
The aim of this thesis was using surface-enhanced Raman scattering (SERS) microspectroscopy for the study of biomolecules and biological systems. The main probe molecule was cationic porphyrin H2TMPyP, however, other porphyrins, tryptophan and two lipids were also used. The sensitivity and reproducibility of several solid SERS substrates: (i) Au and Ag nanoparticles (NPs) immobilized via a bifunctional linker, (ii) AgNPs immobilized by drying, (iii) highly ordered Au and Ag film-over-nanosphere (FON) and (iv) Ag-coated insect wings were compared. On most of the solid substrates, the lowest detected H2TMPyP concentration was ~10-8 M. The highest sensitivity was provided by the dried drops of AgNPs/analyte mixture, where concentrations 1×10-10 M TMPyP, 1×10-5 M tryptophan, 2×10-7 M DSPC and 3×10-7 M DMTAP were detected. Nevertheless, the spectral reproducibility was decreased due to porphyrin metallation and perturbation of the lipid spectra in comparison to their Raman spectra from solution. The highest reproducibility was achieved by AuFON and Ag-coated insect wings. Finally, the AgNPs modified by PEG polymers were tested for intracellular application using HeLa cancer cells. Metallation of H2TMPyP served to probe the accessibility of PEG- AgNPs surface. The results proved that the accessibility...
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Preparation of plasmonic nanoparticles in non-aqueous environments and in water using chemical way and by laser ablation and their testing
Hochmann, Lukáš ; Šmejkal, Petr (advisor) ; Procházka, Marek (referee)
Příprava nanočástic (N) se stala význačnou oblastí chemie díky unikátním vlastnostem, které tyto částice mají a které vedou k širokému okruhu možných aplikací. N se běžně používají v katalýze, elektronice, fotonice a nachází se i v mnoha předmětech běžné denní potřeby. Navíc, vzhledem ke svým plasmonickým vlastnostem, se N ušlechtilých kov· hojně používají ve spektroskopii, kupříkladu při povrchově zesíleném Ramanově rozptylu (SERS). V závislosti na plánovaném použití N lze k jejich přípravě použít více cest. V pří- padě přípravy N v kapalinách (koloid·) lze použít r·zné metody chemické redukce. Tyto metody jsou dobře zavedené postupy, obzvláště ve vodném prostředí. Pro určité aplikace by však byly příhodnější koloidy v jiných rozpouštědlech. Proto je hlavním cílem této práce zhodnotit možnosti přípravy koloid· chemickou redukcí a laserovou ablací ve vodě a organick- ých rozpouštědlech. Dalším cílem je charakterizace připravených částic a zhodnocení jejich potenciálu pro SERS. Zlaté koloidy ve vodě a alkoholech byly připraveny redukcí kyseliny tetracholoro zlatité tetrahydridoboritanem sodným. K přípravě stabilních sol· v alkoholech byl dále nutný pří- davek polyvinylpyrrolidonu (PVP) jako stabilizátoru, protože přímá příprava koloid· chemickou redukcí v alkoholech vedla k jejich kolapsu. Dále...
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Disease and diagnosis of cardiovascular system
Procházka, Marek ; Jelen, Karel (advisor) ; Lopot, František (referee)
Disease and diagnosis of cardiovascular system Abstract In this bachelor's thesis, we are dealing with cardiovascular diagnostic methods and the most common diseases affecting the cardiovascular system. The text briefly introduces the basic diagnostic methods of the cardiovascular system. Furthermore, we focus on the most common heart diseases and possible diagnosis using these methods. Out of these diagnostic methods, we will focus on the CVS method (Classification of cardiovascular system), which is developed by the Institute of Thermomechanics AS CR in cooperation with the Faculty of Physical Education and sport, from which we are expecting in future the prediction of hypertension. This work also serves as a theoretical basis for the future experimental part of the research. Keywords: atherosclerosis, hypertension, diagnostic methods of cardiovascular system, diseases of cardiovascular system, CVS
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Psychological intervention in company management
Procházka, Marek ; Rymeš, Milan (advisor) ; Bahbouh, Radvan (referee)
Paper describes psychological intervention in organization based on Organization Development approach. Theoretical part presents principles, methods and techniques of this discipline, and relevant theory of organization. Key concepts of organizational character, organizational climate and organizational culture are amended with developmental aspect in several theories of organization growth. The principles imply practical advice for implementation of organizational change. This provides theoretical and practical backup for the following intervention. The practical intervention focused on transformation crisis in a production company. Intervention followed action research paradigm with certain practical limitations. Final results are supplemented with recommendations for company intervention derived from practical experience.
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